A user account is required in order to edit this wiki, but we've had to disable public user registrations due to spam.
To request an account, ask an autoconfirmed user on Chat (such as one of these permanent autoconfirmed members).
Video Overlay
<overlay> is a proposal to display and style subtitles/captions for <video> in a uniform way, regardless of whether they are in-band or from an external resource. It also doubles as a container to overlay arbitrary (HTML) content on a <video>, enabling advanced scripted overlays such as karaoke animations or visual annotations.
Background
Use Case Description
Complete description of the use case.
Current Limitations
HTML5 currently lacks convenient markup and interfaces to handle at least three things:
- Syncing and displaying external subtitles/captions with <video>
- Styling in-band subtitles/captions from media resources
- Placing
Current Usage and Workarounds
Some evidence that this feature is desperately needed on the web. You may provide a separate examples page for listing these.
Benefits
Explanation of how and why new markup would be useful.
Requests for this Feature
- Source
I would like this feature ...
Proposed Solutions
My Solution
- Brief description of the solution and of how it address the problem at hand.
Processing Model
- Explanation of the changes introduced by this solution. It explains how the document is processed, and how errors are handled. This should be very clear, including things such as event timing if the solution involves events, how to create graphs representing the data in the case of semantic proposals, etc.
Limitations
- Cases not covered by this solution in relation to the problem description; other problems with this solution, if any.
Implementation
- Description of how and why browser vendors would take advantage of this feature.
Adoption
- Reasons why page authors would use this solution.
References
Silvia Pfeiffer's blog posts:
- More video accessibility work
- First experiments with itext
- The different aspects of video accessibility
- New proposal for captions and other timed text for HTML5
- The model of a time-linear media resource for HTML5
- Manifests for exposing the structure of a Composite Media Resource
Silvia Pfeiffer's <itext> proposals:
Mailing lists:
- re-thinking "cue ranges" from David Singer (Apple)
- timing model of the media resource in HTML5 from Silvia Pfeiffer
- initial <overlay> suggestion from Philip Jägenstedt (Opera) with feedback from Eric Carlson (Apple)